TGListView, TGLVContainer and TGLVEntry
A list view is a widget that can contain a number of items
arranged in a grid or list. The items can be represented either
by a string or by an icon.
The TGListView is user callable. The other classes are service
classes of the list view.
A list view can generate the following events:
kC_CONTAINER, kCT_SELCHANGED, total items, selected items.
kC_CONTAINER, kCT_ITEMCLICK, which button, location (y<<16|x).
kC_CONTAINER, kCT_ITEMDBLCLICK, which button, location (y<<16|x).

Set number of headers, i.e. columns that will be shown in detailed view.
This method must be followed by exactly ncolumns SetHeader() calls,
making sure that every header (i.e. idx) is set (for and example see
SetDefaultHeaders()).